Golf tee

ABSTRACT

An improved golf tee having a ball support surface that reduces the frictional resistance of the tee when the ball is struck thus lengthening the distance a ball can be driven. A friction reducing material such as a fluorochemical or flouropolymer comprises the support surface.

FIELD OF THE INVENTION

[0001] This invention relates to a golf tee specifically designed tominimize the forces of friction and shear between the golf tee and thegolf ball when the ball is struck by a golf club thereby maximizing thetransfer of energy and momentum from the golf club head to the ball.

BACKGROUND OF THE INVENTION

[0002] In the ever increasingly technical world the sport of golf hasseen its share of innovations in the last few decades. Most of thesehave been aimed at either the golf ball or the golf club with a smallernumber directed to the golf tee. Although a number of patents have beenwritten for tee designs, very few have considered the golf tee as asource of improved distance and ball flight. In U.S. Pat. No. 5,683,313and U.S. Pat. No. 5,413,330 Thomas Disco and Charles Parish disclose aVented Golf Tee design. Venting the golf tee is done to reduce thesuction between the surface of the golf tee and the golf ball uponimpact with the club head. In U.S. Pat. No. 5,505,444 Edward Bouclindisclosed a flat head tee designed to reduce friction. In this patent anadhesive material must be applied to keep the ball from rolling off thetee. One might question whether the adhesive force negates any benefitfrom the reduced surface area.

[0003] In U.S. Pat. No. 6,053,822 Jeffery Kolodney discloses a tee witha ring of bristles coming up to hold the ball in place. In U.S. Pat. No.6,004,228 John Adam discloses a Vented Angular Golf Tee, another designto work on eliminating the suction between the ball and the tee. Allthese designs have merit in that they recognize that there are forces atplay between the ball and the tee that can be reduced, altered, orre-directed. Accordingly, it is one object of my invention to minimizeforces associated with the tee that act to resist the energy transferredto the ball from the golf club at impact, while at the same time keepingthe end product practical to use and purchase.

[0004] Minimizing the effect of forces associated with the tee produceslonger flight distances and more initial ball spin due to the club headacting on the ball. These benefits are a primary object of the inventionand are especially desirable for the long shot, where the ability toadvance the ball takes precedence. In addition, the short shot wheremaximum backspin helps to stop the ball quickly on the green isimproved. These and other benefits and objects are achieved by myinvention which is described in the summary of the invention anddetailed description below.

SUMMARY OF THE INVENTION

[0005] I have surprisingly discovered that the flight distance and spinof a golf ball are increased by reducing the surface friction of thesurface of the golf tee on which the golf ball rests. Thus, in oneaspect, my invention is the process of reducing surface friction of thesupport surface of a tee by application a coating or a layer of lowfriction material or low surface tension material comprising, forexample, a fluorochemical material or a fluorocarbon resin such aspolytetrafluoroethylene, perfluoroalkoxy material or their copolymers.The entire tee may be made from a low friction material or only the heador a cap on the head may be made from low friction material.

[0006] In another aspect, my invention comprises a tee with a supportsurface coating of such resins and the support surface area has beenreduced to the least amount of surface area practical. My invention alsocomprises the method of making such a tee.

DESCRIPTION OF THE DRAWINGS

[0007] In the drawings appended hereto and made a part of thisdisclosure:

[0008]FIG. 1 is a top plan view of a golf tee representing of onepreferred embodiment of the present invention;

[0009]FIG. 2 is a side view of the embodiment of FIG. 1;

[0010]FIG. 3 is a perspective side view of showing a partial golf ballpositioned on a prior art tee;

[0011]FIG. 4 is a sectional view of the embodiment of FIG. 2 but with agolf ball positioned on the tee; and,

[0012]FIG. 5 is a side elevation in section of preferred embodiment ofthe present invention showing a golf ball tee in position.

DETAILED DESCRIPTION

[0013] My invention deals with three factors in improving teeperformance:

[0014] 1. The surface material of the tee where the ball is intended torest;

[0015] 2. The minimal surface area of the tee needed to contact theball; and,

[0016] 3. The shape of contact area to minimize shear effects during atee shot.

[0017] The frictional forces acting when an object is resting on asurface can be represented by the equation: F=W×SA×CoF where F is theforce of friction, W is the weight of the golf ball (which is aconstant), SA is the surface area of contact, and CoF is the coefficientof friction of the surfaces.

[0018] In the case of the golf ball the CoF can change depending uponthe cover material used in its construction. Generally, harder ballsknown for their distance have lower CoF's than softer covered balls. Inthe case of the surface of the tee, the preferred support surfacematerial in my invention is polytetrafluoroethylene, or PTFE, which issold under the brand name Teflon®) (DuPont's trademark for this polymermaterial) as the surface of choice. This material or similar materialssuch as FEP (fluorinated ethylene propylene copolymer), PFA(perfluoroalkoxy), or ETFE (ethylene/tetrafluoroethylene copolymer) havethe lowest coefficient of friction of generally available and usablematerials. All contain fluorine in their chemistry. In addition they areknown for providing non-stick surfaces.

[0019] Terms such as fluoropolymer, fluoroplastic, fluorocarbon resin,or fluorohydrocarbon resin may be used in this specification as thepreferred fluorine containing compositions are those which produce lowfriction surfaces or low surface tension surfaces. These compositioninclude those compositions known as “fluorochemicals.” In general,compositions which exhibit low surface friction are within the scope ofmy invention. Low friction tends to be more important when the golfer isusing balata or other soft covered balls that are composed of low Tg(Glass Transition Temperature) polymers that have a tendency to selfadhere more easily to other surfaces than harder polymers such as thosemade from the ionomers sold under the brand name Surlyn® also sold byDuPont.

[0020] Considering the surface area, most conventional or prior art teesare made more or less the same. They consist of a bowl having a diameterof approximately 10 to 13 mm. to the outer edge. In addition, this bowlshape generally has a ball conforming shape ending abruptly at theedges. From a manufacturing standpoint it is clear to see that thisshape offers the golfer the greatest ease when sticking the tee in theground and mounting a golf ball on it. However, from a frictionalstandpoint, the smaller the surface area of contact, the better. Thesmallest area of contact would be a single point, but this would make itvirtually impossible for the golfer to mount the ball. In addition, thehand held ball-and-tee combination is used by many golfers forguidelines and additional force when sticking the tee in the ground anda very small point would be next to impossible to use. Obviously, anychange in the shape of the tee head would have to take intoconsideration these things to be accepted by the typical golfer. Golfingcan be frustrating enough without having to worry about mounting thegolf ball on the tee.

[0021] Referring now to FIG. 1, a top plan view of the tee 1 is shown.The minimum acceptable surface area can be achieved with three points ornobs 2 equal distance apart defined by the dotted line circle 3 inFIG. 1. It has been discovered that the minimum diameter of the centerof the circle is preferably in the range of 5 to 9 mm. If the diameteris less, substantial difficulty is encountered in mounting the ball.Points defined by a larger circle can be used, but shear forces come into play as described below. In addition, the support points 2 should bepreferably short and stubby in configuration to stabilize the ball'sposition when using the golf ball to stick the tee into the ground. Aside view of golf tee 1 with head 4 is shown in FIG. 2 with support nobs2 having the configuration mentioned.

[0022] In addition to frictional forces there are shear forces SF actingon a golf ball that also reduce energy transferred from a club headwhich strikes the ball (See FIGS. 3 & 4). The shear forces SF is theresistance to the initial movement of ball 5 direction against the edge6 of the perimeter of the tee head. A smaller, more rounded perimeterwill provide a smaller surface area thus reducing the total frictionalresistance. Having a shallower resting area will help to minimize theshear force SF since less of the weight WB of the ball is beneath theedge 6. In addition, a rounded smoother edge will produce less shearforce than a sharper more knife like edge. This effect may explain tosome extent the longer distances and better trajectories that are seenwith the balls hit by professional golfers because in a pro swing theclub head contacts the ball on the upswing, and the force imparted has alower horizontal component of the shear force SF. This force asillustrated in the center slice view of conventional ball and tee inFIG. 3 shows why an upswing hit is affected less by the shear force thana straight horizontal swing represented by FC. An embodiment of myinvention to minimize these forces is illustrated in center slice viewof the ball and tee in FIG. 4. It can be understood that a golfer with aswing that contacts the ball on the downward swing would tend to benefitmore from this embodiment, due to the greater shear force SF impartedwith this swing which would impart a vertical component to the forcevector.

[0023] In the embodiment of a tee as described above the tee wouldpreferably be made out of pure PTFE by molding or machining, Example 9but the expense may be unacceptable to the average player. To overcomethe problem of expense and provide the advantages of reduced resistancethe following examples were disclosed.

EXAMPLE 1

[0024] The resting surface of a standard wooden tee was coated with afluorosurfactant, DuPont's Zonyl, to lower the surface tension andfriction of a ball resting on it.

[0025] Observations: The low molecular weight material is easily shearedoff and appears to only last 1 or 2 hits. Also, some material may betransferred to the ball and subsequently the club face which violatesthe following USGA rules:

Rule 4-3. Foreign Material

[0026] Foreign material must not be applied to the club face for thepurpose of influencing the movement of the ball. Penalty isDisqualification.

Rule 5-2. Foreign Material

[0027] Foreign material must not be applied to a ball for the purpose ofchanging its playing characteristics. Penalty is Disqualification.

EXAMPLE 2

[0028] A conventional wooden tee conventional according to FIG. 5 wasused. The FIG. 4 tee could also be used. Surface areas were reduced sothat counterpoint 111 is on a circle with a diameter similar to thediameter of the circle in FIG. 1. The edge of the tee's surface isrounded instead of sharp as shown by the surface from point 111 to edge112. The surface was coated with a DuPont Aqueous Teflon-S Coating, suchas available in the 954 series. This is a water dispersion of DupontTeflon that requires baking to coalesce the polymer particles to acontinuous film. Once the coating is applied, baking is done at 350 to500 degrees F., for 15 to 30 minutes.

[0029] Results: Baking a wooden tee causes the tee to become morebrittle so that it does not last as long. In addition, unless the filmis cast several mills thick the shear of the golf ball coming off thetee during the tee shot abrades the thin film away after only a fewshots.

EXAMPLE 3

[0030] A conventional wooden tee which also could be one modified as inFIG. 5 to reduce the surface area and sharp edges was coated with aDuPont Teflon S coating such as 958-303 or 958-313, a solvent baseddispersion of Dupont Teflon that requires baking to coalesce theparticles to a continuous film. Once the coating is applied the bakingis done at 400 to 600 degrees F., for 15 to 30 minutes.

[0031] Results: Baking continued to be+a problem with the wooden tee.The finished coating is more durable than the water based coatinghowever, a rounded contact surface is still needed to maintain thesurface integrity through several shots.

EXAMPLE 4

[0032] The wooden tee as before was wrapped with a coil film crimpedover the head. The coil film has been coated and baked with the DuPontTeflon dispersions used in Examples 2 and 3.

[0033] Results: The force of the club head striking the ball alsostrikes the head of the tee. This force caused crimping of the coil andfailure after only a few hits.

EXAMPLE 5

[0034] The procedure as in Example 4 and 5 was used where the back sideof the coil is treated with a pressure sensitive adhesive to adhere tothe tee head.

[0035] Results: Although this method seemed to hold up better withseveral tee shots possible, the abrasion of the club head to the backedge of the surface caused failure in the range of 4 to 6 hits.

EXAMPLE 6

[0036] A wooden tee as in the previous examples is capped with a metalcoil bent and cut to the shape shown in FIG. 5. As used herein, “coil”means a relatively thin metal sheet of greater thickness that the commonthickness of metal foil. The metal coil was pre-coated with the DuPontTeflon dispersions mentioned in Examples 2 and 3 and baked at 400 to 600degrees F. for 15 to 30 minutes to coalesce the particles into acontinuous film. The shaped coil part was adhered to the wooden tee witha pressure sensitive adhesive. The coil must be of a soft metal such asaluminum, zinc, copper, or brass to prevent damage to the club head atimpact.

[0037] Results: The force of the club head striking the metal piece wasenough to dislodge it after only a few shots. The metal piece in somecases was separated from the tee and launched with great velocity. Sucha projectile could represent a danger to the golfer or other people onthe course.

EXAMPLE 7

[0038] The procedure as in Examples 6 and 7 where the metal coil ispre-coated with the DuPont Teflon dispersions mentioned in Examples 2and 3 and baked at 400 to 600 degrees F. for 15 to 30 minutes tocoalesce the particles to a continuous film was used. The cut and shapedcoil part was adhered to a wooden tee using a small #4 wood screw.

[0039] Results: This configuration worked well for several shots.However failure occurred usually due to the splintering of the wood teearound the screw again causing the metal coil and/or wood screw to belaunched at a significant velocity. Such a projectile could represent adanger to the golfer or other people on the course.

EXAMPLE 8 Preferred Embodiment

[0040] Several samples of TFPE tape backed with a pressure sensitiveadhesive were obtained from Enflo. These samples differed in theirthickness and ranged from 0.10 mils to 0.30 mils. Wooden tees wereprepared by removing the painted surface from a conventional wooden tee.In addition some tees were shaped to reduce the surface area as in FIG.5. The Enflo tape was cut to fit the tee's shape and applied withpressure. The adhesive was allowed to set for 24 hours.

[0041] Results: This embodiment was the most practical and economicalapproach of the foregoing example. The higher mil thickness tapes hadtoo much memory and were difficult to form on the tee head. However,even the 0.10 mil film lasted at least 15 to 20 hits. It was also notedthat the thicker films tended to become compressed and deformed morereadily than the thinner films.

EXAMPLE 9

[0042] A cylinder of pure PTFE was turned and shaped to produce anotherpreferred embodiment of an improved golf tee. The shape of the headconforms to the top and side views of FIG. 1 and FIG. 2.

[0043] Result: While injection molding would be a preferred massproduction technique to produce the tee of this embodiment, toolingwould be necessary to make the injection mold. The cut part representseffectively the same part that would have been produced by injectionmolding.

[0044] In this preferred embodiment, not only has surface friction beenreduced by the use of a Teflon based material, the surface has also beenreduced to the contact made by the three support prongs or nobs 2. Theprongs being set at 120° provide a sure and stable resting support forthe ball. The diameter of the circle around which the nubs werepositioned was about 8 mm.

EXAMPLE 10

[0045] A wooden tee was dipped in molten PTFE in an attempt to get auniform coating on the head.

[0046] Result: Although other thermoplastic materials like polyethyleneor polypropylene work with this technique, the viscosity of molten PTFEwas too high to effectively form an adhering coating. In addition, thehigh temperature needed to melt PTFE to a fluid or liquid condition weretoo high for a practical process.

Tests

[0047] The tee described in Example 8 was used for comparison against aconventional wooden tee with no modifications. Several tests wereconducted to determine if the tee gave an increase in performance asmeasured by an increase in distance with the tee shot.

[0048] Test 1—Using a 5 wood of 21 degrees of loft ten shots were hitwith range balls mounted on a standard tee and on the tee of Example 9.The 5 wood was chosen for consistency off the tee. The 5 best shots fromeach group were taken and measured for overall distance using a laserrange finding scope with an accuracy of +/−1 yard. The results are inthe following table: Yards with Standard Tee Yards with Tee of Example 91 187 193 2 202 191 3 193 200 4 186 205 5 201. 194 Average 193.8 196.6

[0049] This embodiment yielded an increase in distance of 1.44%. For a250 yard drive this could amount to 3.6 yards.

[0050] Test 2—Using a 5 wood of 21 degrees of loft, several shots werehit with both hard covered distance balls and soft covered balata balls.The 5 wood was chosen for consistency off the tee. Both carry and carryplus roll were measured using a laser range finding scope. The resultsare in the following tables:

[0051] Using Top Flite XL Distance Balls Carry Carry and Roll RegularTee 172.6 yards 182.6 yards Tee of Example 9 176.4 yards 190.0 yardsDifference  3.8 yards  7.4 yards

[0052] Using Titleist Tour Balata Balls Carry Carry and Roll Regular Tee166.3 yards 174.7 yards Tee of Example 9 170.0 yards 182.8 yardsDifference  3.7  8.1 yards

[0053] In both cases whether a hard covered or soft covered ball wasused an increase in carry of 2.2% was achieved. Carry and Roll wereimproved slightly better with the soft covered balls.

[0054] The foregoing results demonstrate that reduction in friction andforces and resistance due to the tee shape do improve performance.

[0055] In another embodiment the entire tee can be made of PTFE so thata cover 114 as shown in FIG. 5 is not required. FIG. 4 shows stillanother embodiment wherein the projections 11 and upper surface of thetee 10 are covered with a PTFE cover 12. The head 14 and shaft 13 aremade of wood. Again, the entire tee can be made of PTFE eliminating theneed for cover 12.

[0056] The foregoing description of the embodiments of my invention areby way of illustration and not limitation. My invention is limited onlyby the scope of the claims below:

What is claimed:
 1. An improved golf tee comprising: a) a support shaft having one end for insertion into the ground; b) a tee head carried by the other end of said support shaft, the top side of said tee head having a ball support surface formed therein; and, c) said ball support surface comprising a low surface friction material whereby a ball mounted on said surface encounters reduced resistance when driven from the tee.
 2. The golf tee of claim 1 wherein said material is selected from the group of polymers consisting of polytetrafluoroethylene, fluorinated ethylene-propylene copolymer, perfluoroalkoxy materials, ethylene/tetrafluoroethylene copolymer, other fluorine containing polymers that provide low friction surfaces, and fluorochemicals.
 3. The golf tee of claim 2 wherein the head of the tee is formed form a material selected from said group.
 4. The improved tee of claim 1 where the ball support surface comprises a central depression having a peripheral rim, said rim having an upper edge which contacts a ball placed thereon in a position to be readily driven.
 5. The improved tee of claim 4 wherein said peripheral rim is circular.
 6. The improved tee of claim 5 wherein the diameter of the circular rim is in the range from about 5 mm to about 9 mm.
 7. The improved tee of claim 1 wherein said support surface comprises three spaced apart projections.
 8. The improved tee of claim 7 wherein said projection are positioned at 120° spacing around said surface.
 9. The improved tee of claim 4 wherein the edge of said rim is provided with a cover made from a material selected from the group of claim
 2. 10. The improved tee of claim 1 wherein the material of the support surface comprises a coating of a fluoropolymer.
 11. The improved tee of claim 1 wherein the material of the surface comprises a layer of fluoropolymer.
 12. The improved tee of claim 10 wherein the polymeric surface is in the form of a covering cap.
 13. In a golf tee, the improvement which comprises a ball support surface comprising a material selected from the group consisting of polytetrafluoroethylene polymer, copolymer, and fluorine containing polymers.
 14. In a golf tee having a ball supporting head, carried by a support shaft, the improvement which comprises a head formed from a low surface tension material.
 15. A process of reducing the surface friction of the support surface of a golf tee comprising the step of coating said support surface with a fluorine containing material. 